3 med. zucchini, cut in half lengthwise
1 onion, thinly sliced
Oil
3/4 tsp. salt
1/4 tsp. pepper
1/2 tsp. oregano
1 can (8 oz.) tomato sauce
8 oz. Mozzarella cheese slices

Saute onion in oil until tender. Add salt, pepper, oregano and tomato sauce. Add zucchini halves and put onion on top. Cover and simmer for 15 to 20 minutes. Top with Mozzarella and place under broiler until cheese melts.